Furnace wall construction



Patented May 30, 1939 UNITED STATES PATENT OFFICE 4 Claims.

This invention relates to furnace walls and the object of the invention is to provide a furnace including a wall about the combustion chamber formed from a plurality of refractory shield blocks so mounted in the wall that the shield blocks may be readily removed and replaced without tearing down the wall.

Another object of the invention is to provide a wall construction in which the supporting blocks for the shield blocks are provided with half-round grooves and the shield blocks are provided with half-round grooves aligning with the grooves of the supporting blocks and providing a round channel which may be filled with cement to lock the shield blocks to the support blocks.

A further object of the invention is to provide a furnace wall in which the shield blocks are supported ush with the surface of the Wall but are provided with air conduits behind the shield blocks whereby the shield blocks are cooled by air flowing through the conduits.

Another object of the invention is to provide a furnace in which shield blocks are provided around three sides of the combustionA chamber and providing air conduits between the shield blocks and the wall whereby air may ow behind the shield blocks on three sides of the combustion chamber.

Another object of the invention is to provide an arrangement whereby air passing through the conduits is directed into the combustion gases above the fire to add oxygen to the combustion gases to support further combustion and reduce smoke.

A further object of the invention is to provide a series of supporting blocks built into the furnace Wall and each provided with a shoulder and a groove, the refractory shield blocks being arranged to be positioned between the support blocks and against the shoulders thereon and the shield blocks being provided with half-round grooves in the top and bottom edges aligning with the half-round grooves in the support blocks and the grooves being lled with refractory cement to key the refractory shield blocks to the support blocks.

A further object of the invention is to provide a construction in which any refractory shield block may be broken out and replaced with a new shield block without disturbing any other part of the furnace wall.

These objects and the several novel features of the invention are hereinafter more fully described and claimed and the preferred form of construction by which these objects are attained is shown in the accompanying drawings in which- Fig. 1 is a cross section of a furnace showingV my improved construction.

Fig. 2 is a section taken on line 2-2 of. Fig. 1. Fig. 3 is a section taken on line 3-3 of Fig. 1. Fig. 4 is an enlarged section through the furnace wall showing the mounting of the shield I blocks.

Fig. 5 is a section similar to Fig. 4 through an alternative form of construction.

A section through the furnace wall is shown in Fig. 4 in which the wall is built up from a. series of courses of brick. Support blocks I are built into the wall and each support block l is provided with a shoulder 2 and with a half-round groove 3 spaced from the shoulder and extending parallel thereto. These support blocks are built into the wall as will be understood from Figs. 1 and 4 and the Wall is constructed so that the next three courses of brick above the support l are set back from the face of the wall to provide a recess. The fourth course 4 is extended out as shown and the next two courses are again set back whilethe third course E above the course d is extended outwardslightly to support the upper support block I. As the wall is built up the refractory shield block 'l may be set onto the lower shield block l. Y

This refractory shield block 1 is provided with a half-round groove 8 in the bottom edge and with a similar half-round groove 8 in the top edge extending parallel with the faces of the shield block. In setting the shield block in position in extends above the face of the support block. The

shield block is then positioned on the Support block as shown in Fig. 4 so that the refractory ,cement 20 remains in the companion grooves 3 and 8 and forms a key between the shield block and support block.

At the upper end the companion faces of the shield block and lsupport block are brushed with Y clay and the groove 8 is filled with refractory cement, at which time, the support block is laid in position so that the refractory cement fills the grooves 3 and 8 at the top of the shield block. The brick courses are then built up above the upper support blocks I as will be understood from Fig. 1. When so constructed, air ducts 9 and l0 are formed between the shield block and the Wall pieces.

Around grooves 3.

proper and these air ducts are arranged to keep the shield blocks cooled by air owing through the said ducts.

As will be understood from Figs. 1 and 2 these ducts are provided about three sides of each combustion chamber and are carried out to a conduit Il shown in Figs. 1 and 2. The conduits II are .carried upwardlyon the outside of the furnace and discharge inwardly beneath the bailie I2 provided between the water tubes I4 of a boilerl for instance. A second baille I5 is provided above the baille I4 so that the products of combustion travel in the direction of the arrows shown in Fig, 3. 'Ihis carries the products of combustion past the discharge end I6 of the duct I I so thatV air is drawn from this duct to support combustion at this point by the addition of oxygen containing air. As will be understood from' Fig. 2 the air enters the front of the furnace and passes through the ducts 9 and Ill where the air cools the shield block 1 and also becomes preheated in taking heat away from the shield blocks. This preheated air 'then passes through the duct II and is discharged through the opening I beneath the edge of Athe baille I Il.

If any of the shield blocks become broken or :burned out and requirereplacement the burned outor broken shield block may be removed either by vbreaking it out or, if broken, by removing the A new'shield block I is then provided and the edges are brushed with clay and the grooves 8 are filled with refractory cement so that as the shield block is moved back into position to bring "thegrooves 8 to alignment with the grooves the refractory cement will iill the grooves 3 and V8 and upon hardening will act as keys to lock the shield block to the support blocks. Thus, the shield block may be removed and replaced without tearing down the wall and without disturbing any portiony of the wall except the shield blocks being replaced.

An alternative form of construction is shown in'Fig. 5 which is used for a wider lire wall. In -this form, a support block II is provided in the central course between the top and bottom support blocks. This support block Il is provided with two shoulders I8 and I9 and with two'half- This center support block I'I is spaced from the top and bottom support blocks so'that a full sized shield block may be mounted above and below the center support block I'l. This forms a higher shield wall and the air ducts above and below the center support blocks I 'I are considerably higher than those shown in Fig. 4. In all other `respects the construction shown in Fig. 5 is the same as that shown in Fig. 4.

From the foregoing description it becomes evident that the construction provides a means whereby the refractory shield blocks may be readily removed and replaced and when mounted in position are firmly keyed in the wall, provides air ducts for cooling the refractory shield blocks and provides a device which accomplishes the objects described.

Having thus fully described my invention, its

utility and mode of operation, what I claim and desire to secure by Letters Patent of the United States is- 1. A furnace wall comprising a built-up wall having a pair of support blocks mounted in the inner face of the wall in vertical spaced relation, each support block being provided with a shoulder on the side toward the other support block and with a groove spaced from said shoulder, the portion of the built up wall between the support blocks being recessed, a shield block arranged to be tted between the support blocks and against the shoulders thereon thereby closing the recess, the shield block being provided with a groove in the top and bottom edge arranged to align with the grooves in the respective support block, the grooves being lled with refractory cement to key the shield block to the support block and the shield block when so mounted covering the recessed portion of the wall and forming a chamber Abehind the Shield block.

2. In a furnace, a built up wall, a pair of support blocks mounted in the inner face of the wall in vertical spaced relation, the Wall being recessed between the support blocks, each support block being provided with a shoulder spaced'from the edge thereof and with a groove extending parallel with the shoulder between the shoulder and the edge, a brick course extending from the wall recess to the vertical plane occupied by said` shoulders, a shield block positioned between the support blocks and against the shoulders of the support blocks, the shield block when so positioned engaging the extending brick course and closing the recess, the companion faces of the support block and shield block being grooved and the grooves being filled with refractory cement to key the shield'block to the support blocks.

3. In a furnace wall, a pair of spaced courses 'of support blocks, each support block being provided with a shoulder and with a half-round groove spaced from the shoulder, a series of refractory shield blocks arranged tobe positioned 'between the support blocks and into engagement blocks mounted in the wall in spaced relation,;

each support block being'provided vwith a groove and a shoulder spaced inwardly therefrom, a refractoryV shield block positioned between the 'support blocks and having grooves arranged to be brought to alignment with the grooves of the support blocks when the shield block is in engagement with the shoulders, the aligned grooves being filled with refractory cement to key the shield block to the support blocks.

ARTHUR C. PACIFIC. 

